Heat activated transfer adhesives, such as thermosetting adhesives available from 3M, St. Paul Minn., are used to bond components of an electrical device together. The thermosetting adhesive is removably fixed to a liner which is wound into roll form. The adhesive is typically unwound and die cut piece by piece into adhesive forms. Each form is then handled manually in two smaller assembly machines, one for pre bonding and one for bonding, this requires two operators manually loading the machines with the adhesive form and parts being bonded together. Handling each adhesive form and part is very time consuming.
In a typical operation, an operator places a first part being bonded into the first machine or fixture, and the adhesive form is aligned and adhered to the one part with the liner facing outwardly. The liner is then removed and the first part is placed into the second machine with a second part. The second machine applies predetermined heat and pressure over a specific time to activate the adhesive and bond the first and second parts together. The process is manual, time consuming, cannot handle die cut parts on a reel well, and can create a lot of waste material.
In addition, when handling the parts and adhesive form manually, guiding features are required in the adhesive liner or the parts themselves to position the adhesive form relative to the parts. The guiding features typically include guiding holes in the liner. The guiding holes can result in usage of more materials since they need to be placed outside the actual part in many cases.